Invalid pad



March 2, 1948. w. T. SIMPSON INVALID PAD Filed Sept. 15, 1944 2Sheets-Sheet l [urn/tor" March 2, 1948.

W. T. SIMPSON INVALID PAD Filed Sept. 15, 1944 2 Sheets-Sheet 2Willa???) Sampson) Patented Mar. 2, 1948 UNITED STATES PATENT OFFICEINVALID PAD William T. Simpson, St. Clairsville, Ohio ApplicationSeptember 13, 1944, Serial No. 553,878

3 Claims. 1

This invention relates to pads and mattresses used by invalid-s andother bed-ridden persons and it has for its primary object to alleviateor to eliminate the pathological effects due to the complete or almostcomplete immobilization of such a person in a reclined position. It is awell known fact that immobilization causes so-.

called bed-soreness, a painful condition which is mainly due to thepermanent 'overburdening of those portions of the body of the patientwhich have to support the weight. Especially these spots suffer mostwhere bones lie close to the skin and Where thin layers of fleshy partsare therefore subjected to heavy pressure from both sides. As aconsequence blood circulation is obstructed or even stopped and thesespots have a tendency to become necrotic. But even in weight carry-- ingportions of the body where conditions are less unfavourable circulationis poor and sub-normal and disagreeable and even disastrous effects arefrequently observed.

The main object of my invention which in tends to provide a remedy forthese unavoidable pathological consequences of immobilization thereforeconsists in the provision of means promoting improved blood circulationin all por tions of the human body resting on the bed or mattress, saidmeans, moreover, permitting to shift the burden due to the weightregularly to other spots. Said means comprise pulsating or vibratingmembers, forming the supporting means for the :body of the patientwhich, by virme of their rhythmic expansion and contraction, produce .amassaging and exercising effect affecting the blood circulationfavourably and entail a change of the weight supporting spots atfrequent intervals.

It is a further object of my invention to provide simple and effectivemeans, adapted for use in beds of every type but especially for use inhospital beds for producing said vibratory or pulsating action, saidmeans preferably comprising a number of elastic and expansible tubesections arranged in close proximity but at a substantial distance fromeach other which are filled with a pressure fluid subjected to periodicand rhythmic pressure variations.

A further object of the invention consists in providing simple andeffective. means for producing the variations in the pressure of thefluid filling the expansible elastic tube sections said means comprisingpreferably a reciprocating diaphragm enclosed in the pressure space of apump which is driven by a motor whose speed is adjustable so that thenumber of pressure variations per time unit and the shifting andmassaging effect can be regulated. With these and other objects to bedescribed below in View, the invention consists in the arrangements,constructions and combinations of parts described by way of example inthe following specification illustrated in the accompanying drawings andenumerated in the claims.

It is to be understood, however, that the spe cific modificationsdescribed and shown are used as an illustration of the inventionand arenot to be interpreted as .limitative.

In said drawings:

Figure 1 is a perspective view of the mattress or pad arranged inaccordance with my invention.

Figure 2 is a cross section through the mattress or pad taken along line2-2 of Figure 1.

Figure 3 is a cross section through the pressure pump with itsreciprocating diaphragm shown at the end of the pressure stroke.

Figure 4 is .a perspective view illustrating a further modification ofthe invention.

In the drawing l designates in a general way the mattress or pad whichis of such size that it can accommodate a person resting thereon; it ishowever to be understood that in special cases where partof the invalidsbody has to be supported otherwise or is not immobilized theconfiguration and the dimensions of the mattress or pad may be chosen inaccordance with the special requirements of the case.

The mattress or pad essentially consists of a lower or base piece 2, andan upper piece or cover 3. The base piece may be made of a solidmaterial such as plastics or it may be made of rubber, while the coveris made of a pliable material such as rubber or a woven fabric, thelatter being preferable when the body of the invalid comes into closecontact with it. Between these two pieces 2 and 3 a system of tubes 4 isarranged consisting of a number of transverse tube sections 5, 5', 5joined to each other at their ends. The connections between saidtransverse sections are preferably made in such a way that a continuoustube is formed meandering through the'interior of the mattress or padfrom end to end.

.One end of the tubing thus formed is closed and may preferably beprovided with a valve 6 permitting the adjustment of the pressure of thefluid with which the tubing is filled, .and the discharge of any excessfluid. A pressure gauge (not shown) may also be mounted on the valve.The other end of the tube system is connected with a pipe 1 leading to apump 3.

The transverse sections 5, of the tube system are made of elastic orresilient material such as rubber which may expand and contract underthe influence of pressure variations imparted to a fluid filling theinterior of the tube. These sections form the body support of themattress. These transverse'sections 5, 5 are arranged at such a distancethat they cannot touch each other even when fully expanded and partitionwalls or ribs l5 of solid material such as plastics or wood may bearranged between them in sub stantial parallelism with the transversesections. Where the lower part 3 of the pad or mattress is made of solidmaterial the partition walls may be formed by ribs integral with saidpart 3. These partition walls or ribs l5 constitute a reinforcement ofthe pad or mattress; they separatethe transverse sections and they areso arranged that their upper edges are approximately at one level withthe upper portions of the transverse sections when the latter aredeflated so that they form the support for the body of the invalidperson when the transverse sections 5, 5' contract to a certain extent.By virtue of this arrangement it is possible to relieve those portionsof the body which rest on the transverse sections of the tubes entirelyat intervals by deflating the said sections to the required extent.

The pump 8, producing the pressure variations of the fluid filling thetube system A may be of any approved type and is shown as a diaphragm.pump, comprising an elastic diaphragm 9 attached to a reciprocatingpiston rod Ill and reciprocated within a pressure space iii of the pump8. The piston rod is driven by an electric motor l3 by means of aconnecting rod ll, attached to its fly wheel l2. The speed of the motoris adjustable in the well known manner by means not shown. Thisregulation of the speed of the motor permits to adjust the variations ofpressure per time unit and thus determines the frequency of thevibrations resulting from the expansion and contraction of the elasticwalls of the transverse sections supporting the body of the invalidperson.

As already mentioned the closed tube system 4, the pipe 1 and thepressure space E6 of the pump are filled with a fluid which is subjectedto pressure variations.

When the motor [3 is' running with a given speed the pressure of thefluid in the pressure space 16 of the pump varies as the reciprocatingdiaphragm alternately narrows and widens the pressure space. During eachcycle of operations the pressure'of the fluid in the pump 8 thusincreases and decreases. These pulsations are transmitted to the fluidin the tube system 4 and the section 5, 5 5" which form the mainoperative parts of said system thus expand and contract in accordancewith these pulsations of the pressure. Therefore these tube sections arealternately pressing against and receding from the body of the personresting on them and this action, when performed regularly and atpredetermined intervals, will exercise a massaging effeet on those partsof the body with which the tube sections are in contact. This exercisingand massaging effect, which is sometimes called passive exercise willpromote and activate the blood circulation.

If necessary the pressure may be so adjusted that during the lowpressure intervals the tube section 5, 5 are deflated to such an extentthat the body no longer rests on them but is rested on the partitionwalls or ribs I5, thereby relieving completely and at regular intervalsthe portions of the body which originally carried the load.

In the modification shown in Figure 4 two tube systems l1, I8 are usedin arrangement which permits an improved distribution of the weight ofthe invalid person. Each system consists of a main tube 20, 2|respectively running lengthwise through the pad or mattress, from whichshorter and closed transverse sections 22, 23 respectively are branchingoil at right angles. The main tubes may be closed at their ends orprovided with the valves, described in connection with Figure 1. Thetransverse sections 22,

' 23 of the two systems are so arranged with respect to each other thatthe tube sections of one system are always placed in the space leftbetween two tube sections of the other system the distance between twoadjacent tubes being always such that the tubes may expand fully withoutever touching each other as clearly shown in the figure.

The entrance end of the main tubes 20, 2| are connected with pipes 26,21 leading to the pump 25, which is identical with the pump described inconnection with Figure 3. Each system may be connected with a separatepump, both being driven by the same motor, but in the modificationillustrated in Figure 4 only one pump 25 is shown supplying a main pipe28 which is connected with the two branch pipes 26, 21. At the end ofeach branch pipe a slide valve 29, 30 is provided which is actuated bythe motor I3 and alternately opens and closes the connection of thebranch pipes 26, 21 with the main pipe 28. The slide valves 25 and 30are of any approved or well known construction and are not separatelyillustrated; they may simply consist of discs provided with ports oropenings closing and opening the connection between the pipes leading toand from the valve casing 30 and 29, respectively. Or they may consistof cylinders provided with ports or openings establishing connectionbetween the aforesaid pipes.

It is, however, to be understood that the ports or openings in the twoslide valves covering or uncovering the communication between the pipesleading to and from the valve casings 29, 30 are symmetrically arrangedwith respect to a vertical plane passing between the two branch or slidevalves and are so positioned that one of the slide valves establishes acommunication while the other closes it. If, therefore, the connectingrod is moved forward one of the two branches, say the branch 26, will beconnected with the pipe 23 while the other is closed and when theconnecting rod 3| is moved backward, the connection which was firstclosed (say the connection through pipe 27) is opened while theconnection which was opened upon the forward stroke of rod 3! (say theconnection through pipe 26) is closed.

The connecting rod 3| is reciprocated in a manner clearly shown in Fig.4 by means of a swinging link whose movement is derived from a discrotated'by the motor I3.

With this system the body of the invalid person alternately rests on thetube sections of one or the other system and therefore one of the mainsources of bed soreness, the permanent pressure of the Weight on thesame spots, is eliminated. Moreover the number of spots which aresubjected to an exercising and massaging action is doubled.

From the above description it will be seen that the invention permitseffective suppression and elimination of some of the detrimental effectsof the immobilization of a completely invalid person. Permanentattendance in view of a frequent change of position is no longernecessary. The main point is however the improvement of the circulationin those parts of the body which are most affected by the heavy pressureof the weight and therefore the invention permits a very markedimprovement of the patients condition.

It is to be understood that the foregoing description has been made withthe intent of illustrating the invention but not of limiting its scopeto the modifications illustrated. The details of the arrangement and ofthe construction of the parts may clearly be further modified withoutdeparting from the essence of the invention.

I claim:

1. A mattress for invalid persons comprising a container, a series ofclosely spaced expansible tube sections filled with a pressure fluid andarranged substantially at the same level, a pump connected with theexpansible tube sections, means for driving the pump, means arrangedwithin said pump for producing periodic pressure variations in saidpressure fluid, inflating and deflating the expansible tube sections,and partition walls inserted between said expansible tube sections insaid container with their upper edges below the level occupied by thetransverse tube sections when inflated during expansion due to pressureincrease but at one level with said tube sections when deflated uponpressure decrease to a predetermined extent.

2. A mattress for invalid persons comprising a container, rigid bodysupports therein arranged in spaced relation, inflatable body supportsarranged between said rigid supports, consisting of elastic tubesections of a diameter smaller than the height of the rigid supportswhen deflated and larger than said height when inflated, said tubesections being joined to form a single system, a pressure fluid fillingthe said system and means including a diaphragm for producing rhythmicalsystem.

3. A mattress for invalid persons comprising a container, a system ofparallel rigid body supporting members in spaced relationship withinsaid container, inflatable body supports consisting of inflatable tubesections arranged in substantial parallelism within the spaces betweenthe rigid supporting members, the diameter of said tubes being smallerthan the heightof the rigid supporting members when deflated and largerthan said height when inflated, and the spaces left between the rigidsupporting members being larger than the diameter of the inflated tubesection, further tube sections arranged substantially at right angle tothe rigid body supporting members, each of these sections joining twosections parallel to said supports, so as to form a single tube systemrunning along and around the supporting members of the rigid supportsystem a pressure fluid filling said inflatable tube system and meansincluding a movable diaphragm for rhythmically increasing and decreasingthe fluid pressure within said inflatable system.

WILLIAM T. SIMPSON.

REFERENCES CITED The following references are of record in the flle ofthis patent:

UNITED STATES PATENTS Number Name Date 1,643,793 Sparhawk Sept. 27, 19271,772,310 Hart .,Aug. 5, 1930 2,112,702 Loibl Mar. 29, 1938 FOREIGNPATENTS Number Country Date 483,111 Great Britain Apr. 12, 1938 483,132Great Britain Apr. 12, 1938

